Abstract: Journal of the Formosan Medical Association 120 (2021) S77eS85 Available online at www.sciencedirect.com ScienceDirect journal homepage: www.jfma-online.com Original Article Assessing efficacy of antiviral therapy for COVID-19 patients: A case study on remdesivir with bayesian synthesis design and multistate analysis Sih-Han Liao a,b,c, Chien-Ching Hung d,e, Chiung-Nien Chen f,g, Jui-Yi Yen h, Chen-Yang Hsu a,i, Amy Ming-Fang Yen j, Chi-Ling Chen a,g,k,* a Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan b Section of Gastroenterology, Department of Medicine, National Taiwan University Cancer Center, Taipei, Taiwan c Division of Gastroenterology and Hepatology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan d Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan e Department of Tropical Medicine and Parasitology, National Taiwan University College of Medicine, Taipei, Taiwan f Center for Functional Image and Interventional Therapy, National Taiwan University, Taipei, Taiwan g Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan h Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan i Dachung Hospital, Miaoli, Taiwan j School of Oral Hygiene, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan k Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan Received 6 April 2021; received in revised form 18 April 2021; accepted 21 April 2021 KEYWORDS Antiviral therapy; COVID-19; Remdesivir; Clinical efficacy; Background/purpose: A synthesis design and multistate analysis is required for assessing the clinical efficacy of antiviral therapy on dynamics of multistate disease progression and in reducing the mortality and enhancing the recovery of patients with COVID-19. A case study on remdesivir was illustrated for the clinical application of such a novel design and analysis. Methods: A Bayesian synthesis design was applied to integrating the empirical evidence on the one-arm compassion study and the two-arm ACTT-1 trial for COVID-19 patients treated with * Corresponding author. Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, 7 Chung-Shan South Road, Taipei, 100, Taiwan. Fax: þ886 2 23709820. E-mail address: chlnchen@ntu.edu.tw (C.-L. Chen). https://doi.org/10.1016/j.jfma.2021.04.026 0929-6646/Copyright ª 2021, Formosan Medical Association. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). S.-H. Liao, C.-C. Hung, C.-N. Chen et al. Bayesian synthesis sequential design remdesivir. A multistate model was developed to model the dynamics of hospitalized COVID-19 patients from three transient states of low, medium-, and high-risk until the two outcomes of recovery and death. The outcome measures for clinical efficacy comprised high-risk state, death, and discharge. Results: The efficacy of remdesivir in reducing the risk of death and enhancing the odds of recovery were estimated as 31% (95% CI, 18e44%) and 10% (95% CI, 1e18%), respectively. Remdesivir therapy for patients with low-risk state showed the efficacy in reducing subsequent progression to high-risk..